diff --git a/browser/base/content/abouthome/aboutHome.css b/browser/base/content/abouthome/aboutHome.css
index c2703180fc10e..016206178d674 100644
--- a/browser/base/content/abouthome/aboutHome.css
+++ b/browser/base/content/abouthome/aboutHome.css
@@ -14,8 +14,8 @@ html {
 
 body {
   margin: 0;
-  display: -moz-box;
-  -moz-box-orient: vertical;
+  display: flex;
+  flex-direction: column;
   width: 100%;
   height: 100%;
 }
@@ -32,7 +32,7 @@ a {
 }
 
 .spacer {
-  -moz-box-flex: 1;
+  flex-grow: 1;
 }
 
 #topSection {
@@ -55,12 +55,12 @@ a {
 }
 
 #searchForm {
-  display: -moz-box;
+  display: flex;
 }
 
 #searchLogoContainer {
-  display: -moz-box;
-  -moz-box-align: center;
+  display: flex;
+  align-items: center;
   padding-top: 2px;
   -moz-padding-end: 8px;
 }
@@ -77,7 +77,7 @@ a {
 }
 
 #searchText {
-  -moz-box-flex: 1;
+  flex-grow: 1;
   padding: 6px 8px;
   background: hsla(0,0%,100%,.9) padding-box;
   border: 1px solid;
@@ -188,9 +188,9 @@ a {
 }
 
 #launcher {
-  display: -moz-box;
-  -moz-box-align: center;
-  -moz-box-pack: center;
+  display: flex;
+  align-items: center;
+  justify-content: center;
   width: 100%;
   background-color: hsla(0,0%,0%,.03);
   border-top: 1px solid hsla(0,0%,0%,.03);
@@ -206,8 +206,8 @@ body[narrow] #launcher[session] {
 }
 
 .launchButton {
-  display: -moz-box;
-  -moz-box-orient: vertical;
+  display: flex;
+  flex-direction: column;
   margin: 16px 1px;
   padding: 14px 6px;
   min-width: 88px;